"We were very happy customers," Ryan Fisher corrected his mother. "After we got sprayed for mosquitoes, we went from looking like we have chicken pox to only getting stung twice more the rest of the year."

Fisher and Anderson were so happy that they shifted from customers to entrepreneurs. They opened a St. Cloud branch of Mosquito Squad last year.

They have a growing client base and 13 employees. The group often gets returning clients and offers a discounted season package of six sprays.

"One guy was so happy, he stepped in to hug me," Fisher said.

Mosquito Squad is now in an important part of the season where mosquito-transferred illnesses are at their peak.

"Mid-July to mid-September is when we are at the biggest risk of mosquitoes," Minnesota Department of Health epidemiologist Dave Neitzel said.

"St. Cloud is right in that transition zone that puts people at risk. There's woodlands to the north and open farm country to the east and west."

Neitzel said Minnesotans are most at risk to contract West Nile virus and La Crosse encephalitis mosquito-transferred illnesses. Some people have allergies to mosquitoes as well.

"It's been a cooler year than normal, so there have been a ton of mosquitoes that we just consider pests," Neitzel said. "The disease ones have been starting to come out the last couple of weeks. We have a shorter season for this virus to grow and be transmitted, but it's important to be cautious."

Health concerns have aided the growing mosquito spraying industry.

"It's a relatively newer industry, but it's proven to be really effective," said Tim Hall, who started St. Cloud-based Minnesota Mosquito Control three years ago.

Hall, like Fisher, started his company after having his lawn sprayed.

"At my cabin it was bad — even during the day," Hall said. "But ever since we started spraying, I haven't got a mosquito bite during the day."

Mosquito Squad and Minnesota Mosquito Control employ similar methods. They charge about $125 an acre for one spraying.

They use pesticides, spraying the perimeter of a property and any trees or plants. The pesticides generally kill any bug the size of a housefly and smaller but are considered safe for children and pets.

Both Mosquito Squad and Minnesota Mosquito Control also offer a natural spray made of various oils that is slightly less effective — it kills about 75 percent compared with 90 percent — but is used around lakefronts and by request.

Spraying at a typical home generally takes 20-40 minutes. When pesticides are used, it remains effective on average for 21 days.

"We make a fence — that's the best way to put it," Fisher said. "It kills on contact. Mosquitoes are lazy and like to land on trees and leaves to get out of the sun. When they land on a tree that's been sprayed, they die."

And the emerging industry is working to combat the summer Minnesota pest that's often jokingly referred to as the "state bird."

"I really enjoy being a people pleaser," Fisher said. "We want to make a difference and allow people to be able to enjoy going outside."

Minnesota mosquito concerns

• West Nile virus: The disease that circulates back and forth between infected mosquitoes and birds came to the United States in 1999 and was found in Minnesota in 2002. The disease can cause life-threatening inflammation of the brain. Minnesota Department of Health epidemiologist Dave Neitzel said the biggest risk is to the elderly during dusk and dawn hours.

• La Crosse encephalitis: The disease is transmitted by mosquitoes through shaded standing water such as that in backyard containers, buckets and old tires. It was discovered on a Minnesotan at a La Crosse, Wisconsin, hospital in the 1960s. The disease can cause nerve damage. Neitzel said La Crosse encephalitis poses the greatest risk to children during daytime hours.